Most Heil heat pumps are manufactured in the United States, although Heil's parent company also has manufacturing facilities in Mexico and Canada. The parent company, International Comfort Products Corporation, is based in Lewisburg, Tennessee.
Under the Heil brand, International Comfort Products sells gas furnaces and air conditioners as well as heat pumps. In 1999, the company became a wholly owned subsidiary of United Technologies Corporation, a conglomerate headquartered in Hartford, Connecticut. United Technologies owns such major aerospace manufacturers as Pratt & Whitney, UTC Aerospace Systems and Sikorsky. It also owns Carrier, which is another leading heating and cooling equipment company.